All strings must be XML compatible: Unicode or ASCII, no NULL bytes or control characters

. XML is a markup language that uses Unicode or ASCII characters to represent text. It is important that all strings used in XML documents are XML compatible, which means that they do not contain any NULL bytes or control characters.

NULL bytes are characters with a value of zero, and they can cause problems when used in XML documents. This is because XML parsers may interpret NULL bytes as the end of a string, which can result in incomplete or invalid data being read.

Control characters are characters that are used to control the formatting of text, such as line breaks, tab characters, and carriage returns. These characters can also cause problems when used in XML documents, as they can interfere with the structure of the document and cause parsing errors.

To ensure that all strings used in XML documents are XML compatible, it is important to carefully check and validate any data that is being used. This can involve checking for NULL bytes and control characters and removing them if necessary. It is also important to use encoding schemes that are compatible with Unicode or ASCII, such as UTF-8 or UTF-16.